<div style="background: #ddd;padding: 30px;">
  {{getParentStr}}
  {{str}}
  <button (click)="send()">子组件的button 点击后 传递数据到父组件</button>
  <button (click)="siblingSend()">无嵌套,兄弟组件传递数据</button>
</div>
